Customs in Sri Lanka
Sri Lanka's Office of Examination is the governmental department that overseas their Customs system. If your shipment comes via air mail, and your parcel or bag is flagged for a duty that needs to be paid or paperwork that needs to be filed, it will be held at the Office of Baggage at whichever airport it arrived at, waiting for the hold up to be rectified. Thankfully the Sri Lankan Customs department handles their processing fairly efficiently so anything that needs to be addressed can be done so without much hold up typically. A good way to help your shipment along when sending it to Sri Lanka is to make sure you have the appropriate paperwork filled out before sending as opposed to waiting until after it gets there.
Security concerns when shipping to Sri Lanka
These is a concern for piracy when shipping via ocean cargo freight liners to Sri Lanka. This concern is often combated by the vessels choosing to employee vessel marshalls on board to help ward off attacks, but this has proved to be somewhat inefficient on some occasions. Sri Lanka's Office of Examination is the governmental department that overseas their Customs system.
Packaging when shipping to Sri Lanka
Your shipping company will be able to furnish you with guidelines for packaging when you are planning to ship to Sri Lanka. They will also be able to give you a list of the items that you can not send there to help to avoid any issues with what you decide to send. Some shippers will even package your items for you and give you all the supplies you need, be it boxes or envelopes, some for a small fee and others as gratis. This naturally varies from company to company so you will want to inquire.